SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bf0185462b7494c95df510172d792bcc80b289305c27b5e1ed56b300b34cfe86' 
  AND token = 'KtjTombgxv4PYybXWfGe9q0aGby1hi3q+kUZyBSWSi4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}